Development of a Non- cyanide Alkaline Bath for Industrial Copper Plating

SUMMARY

A cyanide-free alkaline bath containing sodium potassium tartarate (SPT), and triethanolamine (TEA) has been developed by Hull cell studies to electroplate copper. A trace amount of potassium thiocyanate (KCNS) in the bath solution improved the quality of the copper deposit and also improved the efficiency of the plating process. The developed solution is Eco-friendly with good throwing power and a workable effective current density range. Chromate, zinc and iron (Fe²⁺) in trace amounts did not affect the copper deposit. Copper in the bath is in the complex state with TEA and SPT. A simple conductometric procedure was developed to analyse the solution components of the bath solution. Working conditions and electrolyte composition were optimised for a good quality copper deposit.

Keywords:

• Copper deposits
• Throwing power
• Complexing agents
• Non-cyanide alkaline bath
• plating variables